Ask TFL: Should I Buy a Gas or Diesel Heavy Duty Truck to Tow 10,000 Lbs?

2019 Ram 2500 Heavy Duty Big Horn Mega Cab price pricing

This question is extremely relevant for those of you who are thinking about the heavy duty gas vs diesel for a daily driver. Think about it, fuel mileage vs flexibility. Towing capability over the initial purchase price. It’s quite a conundrum.

A viewer recently posed this question to us where he is dealing with this exact question: gas vs diesel heavy duty? He currently has a Ram 1500, but it’s not quite cutting the mustard. He needs a bigger and heavier truck.

2019 ram 1500 rebel hd power wagon
Ram 1500 Rebel or Ram HD Power Wagon?

Here’s the email:

Hi TFL Truck team,

I watch your videos and just think they are the best.  Real world guys testing out the trucks in real world tests.  

I am soon in the market for a new truck. I currently have a 2009 Dodge Ram 1500 Hemi V8.  I am looking to upgrade back to a 2500 HD.  I would like to get the Cummins power plant but my wife is saying it is too expensive (fuel prices here in PA) and says I should get a gas truck.  My dilemma is that I use my truck for a commuter vehicle (76 mi. everyday), plus I occasionally tow my dump trailer and always try to max it out.  My 1500 gets me around 18 mpg when I only use it for commuting but drops way down to under 10 when towing.  But the big thing the 1500 doesn’t have that the 2500 does is the tow rating to pull my dump trailer at its max capacity.  

2019 Ram 2500 Tradesman Power Wagon package
2019 Ram 2500 Tradesman with a Power Wagon package

What I would like you guys to do for me is a comparison of the Ram 2500 Cummins and Hemi V8 on your fuel mileage loop both empty and pulling a 10,000-14,000 lb trailer.  So there would be the fuel mileage empty for both and the fuel mileage loaded for both.  The 2500 Ram that I am looking at getting is the Mega Cab version 4×4, if you can get this version to do your comparison that would be cool.   After you do the Ram then you can probably do the same kind of testing with the Chevy 2500 and Ford F-250.
Thanks and keep up the great videos!


First thing first. We truly appreciate the email and we’ll do our best to help you with an answer. We recently did a video which illustrates (among other things) the efficiency of the Ram 2500 gas engine – in a Power Wagon.

We also produced a video with the Ram 2500 Cummins vs Chevy and Ford on our MPG loop. That was done a year ago.

Check out our 2019/2020 heavy duty buyers guide (here).

You may be able to come to a few conclusions with these videos, but the Ram 2500 gas AND diesel have gone through some changes this year and there’s every reason to believe that their overall efficiency numbers have improved.

With that being said, we do have an answer based on what we already know about heavy duty gas vs diesel trucks: the bottom line is the diesel will do better at towing MPG with a trailer over 10,000 lbs, but the new 2019 Ram 2500 HD Gas with new 8-speed automatic will be a great combination as well, and you don’t have to pay $8K-$9K for the diesel engine.

2018 Ram 2500 Heavy Duty Lonestar Silver

If you tow more – the diesel is the smart choice. If you don’t tow as much, the gas is a good choice and will save you a ton of buyer’s cash. Either way, we suggest you test the rigs you’re interested in back-to-back. Drive them on the same roads, see which one adapts to your driving personality.

As for the video request, this is a great suggestion for the new 2019 / 2020 Ram HD truck we are in the process of testing. We need to get all of our ducks lined up, but we will attempt to do this once the opportunity arises.

Thank you again for your email.

Easily amused by anything with four wheels, Nathan Adlen reviews vehicles from the cheapest to the most prestigious. Wrecking yards, dealer lots, garages, racetracks, professional automotive testing and automotive journalism - Nathan has experienced a wide range of the automotive spectrum. Brought up in the California car culture and educated in theater, childhood education, film, journalism and history, Nathan now lives with his family in Denver, CO. His words, good humor and video are enjoyed worldwide.